NASA is adapting tiny laboratories embedded in compact
discs (CDs) to conduct biological tests aboard the
International Space Station and to eventually look for life on
other planets.
The CDs, with imbedded biological tests, are under evaluation
by NASA scientists, and several academic and industrial
partners. The miniature laboratories were adapted to detect
life forms and chemicals derived from life. NASA’s partners
are Stanford University, Stanford, Calif.; Nanogen, Inc., La
Jolla, Calif.; and the University of California, Irvine,
Calif.
“This type of technology will enhance the International Space
Station capability as a biological laboratory with greatly
increased throughput and state-of-the-art techniques,” said G.
Scott Hubbard, director of the NASA Ames Research Center
(ARC), Moffett Field, Calif. “Someday, this technology could
allow astronauts or robots to search for life on other planets
or moons,” Hubbard said.
To process the CDs, the researchers adapted a suitcase-sized
prototype instrument undergoing laboratory trials at ARC.
There are two versions of the CDs, which are about the same
size as music CDs. One is plastic, similar to a standard CD,
and is disposable. The other is made of glass and is reusable.
“These tiny labs on CDs allow you to do thousands of tests of
biological samples quickly and in the field,” said Michael
Flynn, a scientist at ARC. “On the Space Station, the types of
tests you would do are DNA analyses,” Flynn said.
To begin a test, a scientist places a liquid sample into a
small opening near the center of the CD. The researcher puts
the disc in the prototype machine that spins the CD.
Centrifugal force spreads the sample fluid from the center of
the CD through tiny, capillary-like pipes and valves towards
the outer edges of the disc and several clear observation
areas.
During the journey, special dyes in the CD combine with the
sample. The dyes glow when exposed to specific proteins and
other chemicals, including particular portions of DNA. The
instrument shines a specific color light on the specimen, and
if it glows in another specific color, the specimen contains
the substance the dye was designed to detect. The CD system
can even sample water, and the instrument’s software has image
analysis capability that can discriminate between cells and
debris. A microscope and digital camera built into the
prototype instrument take images of the glowing test sample in
the clear observation area after the disc stops spinning.
“There’re already thousands of fluorescent test solutions
available for conducting biological tests on bacteria,
proteins, viruses and other life-related chemicals,” Flynn
said. “The lab-on-a-CD system allows us to automate a process
that traditionally was very time-consuming and expensive.”
The next step in evaluation of the prototype is to develop
more tests to determine how well the device works. Eventually,
researchers want to add a multi-disk changer to the
instrument, so it can test several CDs.
“We have worked with many different commercial vendors and
individuals to combine a variety of commercially available
technologies into an integrated microgravity-compatible
instrument,” Flynn said. Potential spin-offs could be clinical
uses in hospitals, physicians’ offices and laboratories.
NASA’s Fundamental Space Biology Division, Office of
Biological and Physical Research (OBPR), Washington, funds
this research. Publication-size images are available at:
http://amesnews.arc.nasa.gov/releases/2003/03images/biolabs/biolabs.html
Broadcast-quality sound files of interviews suitable for radio
broadcast are at:
http://amesnews.arc.nasa.gov/audio/biolabs/biolabs.html
More information about OBPR and space research is available
at:
http://spaceresearch.nasa.gov/
